The plane - US Airways Flight 1267 with 69 passengers and five crew members on board - was over Harrisburg when it was ordered to return to Philly. It landed at 8:30 a.m. and was directed to a remote location of the airport, said Chief Inspector Joe Sullivan.
A Philadelphia police SWAT team, along with bomb technicians from the city and the FBI, boarded the plane and removed Shell and his carry-on luggage. They also swept the plane for explosives.
"He was obviously very alarmed as I would be if heavily armed police officers entered a plane to take me off," Sullivan said. "He was certainly stunned."
It was quickly determined that there were no explosives on the plane and that Shell had nothing illegal, police said. He was allowed to fly to the Dallas/Fort Worth International Airport.
"All indications are this was a hoax and a pretty nasty trick was played on a passenger, and it resulted in a threat to, really, all of the passengers," Sullivan said.
His next arrest, however, did not stem from a hoax.
Once the plane landed, Shell was taken away in handcuffs, this time for outstanding warrants from law-enforcement agencies in the Dallas/Fort Worth area, said DFW Airport spokesman David Magana.
Shell was found guilty in Texas in 2006 of possession of a controlled substance and was sentenced to 15 months' probation, court records said. Records also indicate that Shell was convicted of theft in New Jersey and sentenced to 24 months' probation, but it was unclear when that occurred. It was also unclear what led to the arrest warrants.
Shell lives in Philadelphia, according to his Facebook page, and was celebrating his birthday with a trip to his hometown of Keller, Texas, just outside of Fort Worth.
At the airport, he ran into a neighbor working in the security line, according to his Facebook wall: "I'm not going to lie, I feel Blessed [one] of my new neighbors works Security at PHL airport, walked me right in str8 though [sic] security with a breeze."
About 30 minutes into the flight, though, his day took its first turn for the bizarre.
"Im [sic] not going to lie," he wrote on Facebook, "I'm pretty disappointed in US Airways currently. We just spent a half hour in the air to be notified that the plane, 'has technical difficulties' and had to fly back! Flight 1267 CANCELED. Gay!"
Reports varied as to the source of the hoax. Some speculated it was a birthday prank played on Shell. Other reports claimed it was a jilted ex-girlfriend, while some claimed it was a love triangle involving Shell, his ex and his ex girlfriend's new beau.
Thursday night, Frank Burton Jr., spokesman for the Philadelphia division of the FBI, declined to say whether the agency had anyone in custody.
However, a Philadelphia police source said that the FBI had two people in custody for questioning, but declined to identify their relationship to Shell.
Of the 69 passengers aboard Flight 1267, 60 traveled on the same plane to Dallas-Fort Worth once it was cleared for take-off at 11:14 a.m., said US Airways spokesman Todd Lehmacher.
He said with aviation fuel running more than $3 a gallon, the cost of the hoax to US Airways will be high.
"We won't have true costs calculated for some time, but there are upward of tens of thousands of dollars in direct and indirect costs," Lehmacher said.
Whoever is responsible for the hoax will face "severe" federal charges, said Richard Quinn, assistant special agent in charge of national security for the FBI's Philadelphia office.
John Gagliano, a pilot and lawyer with the Wolk Law Firm in Philadelphia, which deals strictly with aviation law, said those responsible will likely be charged with a federal offense that prohibits providing false information that might endanger the safety of an airplane in flight. He said that offense is a felony punishable by up to 20 years in prison.
As for Sullivan, he was glad that everyone was safe and that no first-responders were injured racing to the scene.
"It certainly was a very harrowing day for the gentleman and the passengers," he said. "And it certainly was an expensive day."
- Staff writer Morgan Zalot contributed to this report
Contact Stephanie Farr at firstname.lastname@example.org or 215-854-4225. Follow her on Twitter @FarFarrAway. Read her blog at PhillyConfidential.com.